Mechanical grinding stone



Dec. 3, 1946. j D A J, FORD 2,412,141- l MECHANICAL GRINDING STONE FiledMay 7, 1945 WWW INVENTOR.`

Patented Dec. 3, 1946 OFFICE MECHANICAL GRINDING STONE Asa J. Ford,Kansas City, Kans.

Application May 7, 1945, Serial No. 592,455

2 Claims.

This invention relates to grinding equipment of the type employed insharpening tools, and the primary aim is the provision of such equipmentwherein the abrading stone is moved through its path of travel by powerdriven elements, all to the end that the operator may hold the toolbeing sharpened in a stationary condition while the cutting edge isbeing formed thereon.

One of the important objects of this invention is to provide amechanical grinding stone, the nature whereof permits mounting the sameon a work bench where actuation of the movable parts may be causedthrough the application of power from a small motor.

Other objects of the invention include the provision of a grinding stoneof the aforementioned type wherein the stone is held for travel throughan orbital path; the support for the stone comprises a housing for atrain of gears specially designed to motivate the stone; the stone maybe easily removed without manipulating set screws, clamps or othermanually operable instrumentalities; the stone and its holder ispositioned close to a supporting rail designed to steady the operatorshand and the work; and the support for the stone is in the nature of atablel adapted to house the gear train through the medium whereof poweris applied.

Other objects of the invention will appear during the course of thefollowing specification, referring to the accompanying drawing, wherein:

Fig. 1 is a top plan view of the mechanical grinding stone embodying thepresent invention, parts being broken away for convenience ofillustration.

Fig. 2 is a vertical longitudinal sectional view taken on line II-II ofFig. 1; and

Fig. 3 is a fragmentary vertical central sectional view showing themanner of connecting the equipment to a source of power.

It is common knowledge that workmen have heretofore sharpened tools ofall description by drawing the same over the surface of abrading stonesand that the movement imparted to the tool being treated, is usuallythrough a path of travel substantially orbital or in part, arcuate.Unless the tool is held at a precise angle and with skill and knowledge,the edge created is not true and the beveled portion is not of a formthat produces best results.

To overcome this human element and to insure uniformity of pressure,movement and results, the mechanical grinding stone illustrated in theaccompanying drawing has been designed. Only the preferred form of theinvention has been Vand extending vertically therethrough to a pointbeneath table I0 where bevel gear 22 is affixed thereto. This bevel gear22 is in mesh with another bevel gear 24 on shaft 26, journalled inbearing 28. A pulley wheel 30 on shaft 26 is the medium through whichpower may be applied to the train of gears I4, I6 and I8. A V-belt maybe passed over pulley 30 and thence over a pulley on a motor or othersource of power, not here shown.

Gears I4 and I8 each is providedwith a peg 32 disposed eccentricallywith respect to the center of rotation and these Apegs projectvertically and upwardly through openings 34 formed in a platform 36constituting the top -of the table. This platform 36 has a smooth,horizontal upper surface over which holder 38 may ride when the grindingstone is in operation. Holder 38 has sockets 48 to receive therespective pegs 32 and a grinding stone 42 is secured in any suitablefashion to holder 38, to the end that the upper-surface thereof ispresented for use.

A rail 44 is mounted on platform 36 and extends longitudinally along oneedge thereof and adjacent to stone 42 where the operator mayconveniently employ the same as a rest for his hand as the tool is heldagainst stone 42.

When power is applied the train of gears having elements I 4 and I 8therein will serve to rotate pegs 32 through like circular paths tosmoothly shift holder 38 and the stone 42 along a path of travel that iskindred to the path which is normally established by the tool when beingsharpened through the conventional hand method. The operator need onlyhold the tool at the proper angle, whereupon stone 42 will functionwithout the expenditure of the operators energy other than that requiredto hold the tool against the face of stone 42 with the required amountof pressure.

Advantages arising from a mechanical stone grinder made as abovedescribed, will be obvious to those skilled in the art, and they willlikewise understand that modifications may be made without departingfrom the spirit ofthe invention or scope of the appended claims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. A mechanical grinding stone comprising a table having a flat,horizontal top provided with openings in the latter; agrinding stoneslidably mounted on the table top and having sockets formed in thebottom thereof; a power driven shaft carried by the table; a train ofgears beneath the table top; pins, eccentrically mounted on at least twoof the gears and projecting upwardly through the'openings in the tableltop `and into the sockets of 'the stone holder; `and structureoperatively interconnecting the shaft and the train of gears to rotatethe pins whereby to slide the stone holder through an orbital path overthe table top.

2. A mechanical grinding stone comprising a table having a flat,horizontal top provided with '15 ing stone is being used.

openings in the latter; a grinding stone slidably mounted on the tabletop and having sockets formed in the bottom thereof; a power drivenshaft carried by the table; a train of gears beneath the table top;pins, eccentrically mounted on at least two of the gears and projectingupwardly through the openings in the table top and into the sockets ofthe stone holder; and structure operatively `interconnecting 'the fshaftand the trainof gears to rotate Athe pins whereby to slide the stoneholder through an orbital path over the table top, said table top havinga stationary rail thereon adjacent to the stone holder for supportingthe hands of the user as the grind- ASA J. FORD.

